Where would I report a Inncome Loss of Sale of a Vechkic;le

[DoninGA]

If this was a personal vehicle, not used in a business, the loss on the sale is not reported on a tax return.  Only if you had a gain on the sale would that need to be reported.

[SharonD007]

You don't enter the loss from a personal vehicle sale on your tax return, you only report if you sold it as a gain.  

If you sold your business vehicle, it is reported on Form 4797 Sales of Business Property, which flows to Schedule D - Capital Gains and Losses.

Refer to the TurboTax Help article How do I edit the sale of a business property (Form 4797) for navigation instructions and select Sales of business or rental property that you haven't already reported to report your business vehicle sales.

@Klick6900